Information transfer from a dielectric sheet



Get. 13, 1970 w, 1, ROGERS 3,534,395

INFORMATION TRANSFER FROM A DIELECTRIC SHEET Filed Dec. 27. 1966 2 Sheets-Sheet 1 c020 0 .1 COED TQQA/JPOFT pEeFakpr/0N -1j CWiD Q5005? Paws/e su 17v VE/V roe 71701.00 I. Boss/e:

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INFORMATION TRANSFER FROM A DIELECTRIC SHEET Oct. 13, 1970 2 Sheets-Sheet .3

Filed Dec. 27. 1966 WW MW INVENTO/Q W01. 00 I. R 065/2:

United States Patent 3,534,395 INFORMATION TRANSFER FROM A DIELECTRIC SHEET Waldo I. Rogers, Sierra Madre, Calif., assignor to Rusco Industries, Inc., Los Angeles, Calif., a corporation of Delaware Filed Dec. 27, 1966, Ser. No. 604,695

Int. Cl. G01d /06, 15/08; G06k 7/00; H0111 43/08 US. Cl. 235-61.11 3 Claims ABSTRACT OF THE DISCLOSURE Disclosed method and apparatus enables retrieval from a dielectric sheet of information stored in the form of perforations, as for example pin-hole perforations. The sheet and electrodes are relatively displaced, and electrical arcing or other electrical conduction is effected via the perforations without the electrodes penetrating through the perforations. Especially adapted readout apparatus is also provided, that apparatus including light emitters connected to the electrodes and circuitry including photocells to detect light emission by the emitters.

This invention relates generally to information transfer, and more particularly concerns improvements in the retrieval of data on media such as tabulating cards or paper tape, or the like.

While the invention has a wide range of utility, it finds special utility in connection with retrieving information from dielectric sheets in which relatively small perfora tions have been made in accordance with the teachings of that certain Ballard application for US. Letters Patent Ser. No. 506,094 entitled Perforation of Tabulating Cards. As disclosed in that application, information may be rapidly and advantageously stored in dielectric sheets as by effecting flow of current through the sheet to form small perforations at selected locations. It is a major object of the present invention to provide method and apparatus for retrieving such stored information as by detecting the presence and location of small perforations formed in that manner, although the invention also has advantageous application to detecting the presence and location of larger and conventionally formed perforations.

Basically, the method provided by the present invention includes effecting relative displacement between the perforated dielectric sheet and electroding, and effecting electrical arcing or other electrical conduction through the perforations via the electroding as the latter is brought into close proximity to the perforations. As regards the apparatus itself, the electroding may for example have fingers spaced apart in correspondence to the spacing of rows of perforations on the sheet for close exposure to the sheet along the rows during relative movement of the sheet and electroding, the fingers sized to directly face the perforations without penetrating through them. In this regard, the fingers may advantageously include terminals adapted to wipe against the sheet having perforations so small in relation to the finger terminals as to block penetration of the terminals through the perforations. The latter may for example have been formed by electric arc passage through the sheet as described in that certain Ballard application referred to above.

Further objects and advantages of the invention include the provision of a source of voltage electrically connected with the read electrodes to produce current flow through the pre-formed perforations but not through the dielectric material itself; the provision of light emitters connected with the electrodes selectively to emit light in response to current flow through the fingers and perforations; the provision of photocells, relays and cirouitry to operate the relays in response to photocell detec- Patented Oct. 13, 1970 tion of light emission by the emitters; and means to effect relative movement of the sheet and read electrodes in the manner to be described.

These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following detailed description of the drawings, in which:

FIG. 1 is a block diagram showing the overall system;

FIG. 2 is a plan view showing the manner in which relative movement of the dielectric sheet and electrodes may be effected;

FIG. 3 is a section taken on line 3-3 of FIG. 2;

FIG. 4 is an enlarged perspective showing of a typical electrode with its terminal; and

FIG. 5 is a circuit diagram showing one preferred form of reader circuit.

Referring first to FIGS. 1 and 2, the dielectric sheet may take the form of an ordinary tabulating card 10 having rows and columns of numbers or other indicia. The latter may typically have been subjected to perforation in accordance with the above referred to Ballard application, thereby to form pinhole perforations as better indicated at 11 in FIG. 2, such perforations corresponding to the information to be transferred or retrieved from the card or sheet. Further, such perforations extend in rows parallel to the direction of travel of the card indicated by the arrow 12 in FIG. 2. The block 13 in FIG. 1 indicates the apparatus and method of card perforation in accordance with the teachings of the Ballard application.

The card transport apparatus is indicated generally at 14 in FIG. 1, and it may for example include upper and lower rotary members 15 and 16, as better seen in FIGS. 2 and 3. Each of such members may for example include a series of rollers 17 spaced along and carried by a shaft 18 subjected to rotation by a suitable motor embodied in the card transport apparatus 14, or by hand, thereby to advance the card to the left. The card travels along and in contact with the surface 19 of a support plate 20.

In accordance with the invention, means including electrodes are located to effect conduction through the perforations 11 via the electrodes whenever relative movement of the card and electrodes brings the latter into close proximity to the perforations. In the example illustrated, the electrodes generally indicated at 21 have fingers 22 spaced apart laterally in correspondence to the lateral spacing of the rows of perforations on the sheet, to enable close exposure of the electrodes to the sheet along the rows of perforations during relative movement of the sheet and electrodes. In this regard, the electrodes may be carried as by an insulative support 23 extending transversely over the sheet or card 10. Furthermore, the fingers are sized to closely directly face the perforations without penetrating through them. In this regard, the fingers may include terminals 24, as better seen in FIGS. 3 and 4, which are adapted to wipe against the sheet, and which are sized in such relation to the small perforations 11 as to be blocked by the sheet from penetrating through the perforations; however, if the holes are standard punched holes, the finger terminals may be sized to penetrate them for reading of ordinary punched I cards, increasing utility of the apparatus. The terminals 24 are illustrated to have the advantageous form of pads suitably attached at 25 to the fingers 22, the latter having flat spring tension to urge the terminal pads into light wiping contact or engagement with the upper surface of the dielectric card 10.

Sufficient voltage is applied as via the leads 26 connected with the electrodes as to produce current flow through the perforations, as for example may be enhanced by the carbonized pepirhepry of the are formed perforations, whenever the terminals 24 directly overlie the latter. Such current flows between the terminals and the plate 20. However, the voltage application is insufficient to cause electrical arcing or conduction through the dielectric material of the card.

The apparatus may further be considered to include circuit means selectively to detect the occurrence of current flow through the perforations, as described above.

Referring to FIG. 5, such circuit means may typically include light emitters 28 connected with the electrodes 21 selectively to emit light in response to current flow through the fingers and perforations. In this regard, note the parallel branches each of which includes an electrode 21, a light emitter 28 and a suitable resistor 29, the branches being connected across the high voltage supply 30 as via the lead 31, the plate 20 and the return lead 32. A switch 33 in series with lead 31 is operable to energize the reading circuit. In this regard, a portion of the card reader circuit is indicated in block form at 34 in FIG. 1. Block 35 generally indicates the power supply and card transport control operatively connected with the other blocks as indicated.

The detection circuit means is also shown in FIG. 5 to include photocells, relays, and circuitry to operate the relays in response to photocell detection of light emission by the emitters 28. Mechanization of the latter may include the group of photocells 36 respectively placed sufficiently close to the emitters 28 as to detect light emission from the latter. The photocells are connected between the voltage terminals 37 and 38 via the indicated leads. A series of relays is shown at 39, one for each photocell. Circuitry 40 is also provided to operate the relays in response to photocell detection of light emission. Such circuitry may advantageously include the transistors 41 having base, emitter, and collector electrodes 42, 43 and 44. Each base electrode 42 receives bias via resistor 145, and which is changed in response to photocell energization to increase the base bias sutficiently to cause the transistor to conduct. Upon such conduction, the relay coil 45 connected in series in the collector 44 is energized to close the relay contacts 46, and 47, thereby producing an output readout signal at terminal 48. Such a signal indicates the detection of a perforation in the card. A suitable diode 49 is connected across the coil 45 to suppress inductive transients upon release of the relay contacts and de-energization of the photocell 36.

Adjustment of the AC. high voltage supply 30 may be suitably provided as by the wiper 50 adjustable along the coil 51 connected across the input voltage terminals 52, 53. Closure of the switch 33 may be effected by energization of a relay coil 54, the relay including the switch arm as indicated. Such energization of the coil 54 may be effected by closing the switch arm 55 against the contact 56 which is connected with a suitable source of voltage via terminal 57. A source of voltage may also be connected with terminal 58 for supply to the contacts 46 of the relays 39, whereby when the contacts are closed the voltage may appear at the terminals 48.

From the foregoing it may be seen that the readout signals may be provided at a voltage which is isolated from the high voltage used in producing the electrical conduction through the sheet perforations.

I claim:

1. In apparatus for transferring information, the combination comprising a dielectric sheet, the sheet having electrically conductive paths including rows of perforations therethrough corresponding to the information to be transferred, means including a group of finger electrodes located to effect electric current flow through the sheet via said paths with the electrodes remaining at one side of the sheet and whenever relative movement of the elec trodes and sheet brings the electrodes into close proximity to said paths, said means including another electrode at the opposite side of the sheet and a voltage source remaining in current supplying connection with one of the electrode group and other electrode during said relative movement, the finger electrodes being spaced apart in correspondence to the spacing of said rows of perforations on the sheet for close exposure to the sheet along said rows during relative movement of the sheet and electrodes, the fingers having fiat terminals of a size to closely directly face the perforations without penetrating therethrough and to engage the sheet about the perforations, the terminals being yieldably urged into wiping contact with the sheet, circuit means selectively to detect the occurrence of current flow through said paths, and means to effect said relative movement of the sheet and electrodes, said circuit means including light emitters connected with said electrodes selectively to emit light in response to current flow through the finger electrodes and paths, the circuit means also including photocells to detect light emission by the emitters, re ays and circuitry to operate said relays in response to said photocell detection of light emission.

2. The combination of claim 1 in which said source of voltage is of sufiicient magnitude to produce said current flow through the paths, but not through the dielectric sheet material.

3. The combination of claim 1 wherein said sheet comprises a tabulating card.

References Cited UNITED STATES PATENTS 1,997,178 4/1935 Johnson 23561.603 X 2,379,197 6/1945 Stubbins 200 46 2,422,149 6/ 1947 Unkles et al. 20046 X 2,941,718 6/1960 Lubkin 235-61.116 3,044,694 7/1962 Davidson et a1. 23561.116 3,419,886 12/1968 Ortlieb.

3,189,731 6-/1965 Bowman 235-6l.1 16 3,373,270 3/1968 Fenner 23561.l1 X 3,344,412 9/1967 Goodale et a1.

DARYL W. COOK, Primary Examiner R. M. KILGORE, Assistant Examiner U.S. Cl. X.R. 

